Lecture 2

Question 1

What is the definition of selective breeding

Answer 1

Programs and procedures designed to modify traits in domesticated species

Also called artificial selection

Nature chooses parents in natural selection while breeders choose in artificial selection

Breeders choose desirable phenotypes (think dog breeds)

Question 2

What is the definition of biogeography

Answer 2

Study of the geographical distribution of extinct and modern species

Isolated continents and island groups have evolved their own distinct plant and animal communities

(Example: Island Fox which has evolved from the mainland gray fox

Question 3

What was correlated with major animal groups evolution?

Answer 3

Evolution of major animal groups correlated with known changes in the distribution of land masses on the Earth

Think about how the first mammals arose 200 million years ago when Australia was still connected

Placental mammals arose 80 million years ago after Australia separated

Australia has no large, terrestrial placental mammals; instead has marsupials, most of which aren’t found elsewhere

Question 4

What is the definition of convergent evolution

Answer 4

Two different species from different lineages show similar characteristicd bc they occupy similar environments; species are not closely related evolutionares

Question 5

What is the definition of homology

Answer 5

Fundamental similarity due to descent from a common ancestor.

Homology may be:
- Anatomical
-Developmental
-Molecular

Question 6

What is Anatomical homology

Answer 6

Same set of bones in the limbs of modern vertebrates has undergone evolutionary change for many different purposes

Homologous structures are derived from a common ancestor

Question 7

What is Vestigial Structures

Answer 7

Anatomical structures that have no apparent function but resemble structures of presumed ancestors

Question 8

What is Developmental homology

Answer 8

Species that differ as adults often bear striking similarities during embryonic stages

Presense of gill ridges in human embryos indicates that humans evolved from an aquatic animal with gill slits

Human embryos have long bony tails

Question 9

What is molecular homology

Answer 9

Similaries in cells at the molecular level show that living species evolved from a common ancestor

All living species use DNA to store information

Certain biochemical pathways are found in all or nearly all species

The same type of gene is often found in diverse organisms

Sequences of closely related species tend to be more similar to each other than to distantly related species